BioSenic SA

Share Issue/Capital Change • Oct 5, 2023

PRESS RELEASE – REGULATED INFORMATION 05/10/2023

Information on the total number of voting rights and shares

Mont-Saint-Guibert, Belgium, October 5, 2023, 7.00 am CEST – BIOSENIC (Euronext Brussels and Paris: BIOS), the innovative company addressing unmet medical needs in in the areas of innate immunity, inflammation and organ/function repair, today announces an increase in the total number of voting rights and shares as a result of the issuance of new shares following the conversion of convertible bonds. The following information is published in accordance with article 15 of the Belgian law of 2 May 2007 on the publication of major shareholdings in issuers whose shares are admitted to trading on regulated market.

Total amount of share capital on August 31, 2023	EUR 34 500 669
Total number of shares with voting rights on August 31, 2023	137 348 141
Total number of new shares issued between September 1, 2023 and September 30, 2023	25 833 333

Total amount of share capital on September 30, 2023	EUR 35 100 669
Total number of shares with voting rights on September 30, 2023	163 181 474
Total number of voting rights (denominator) on September 30, 2023	163 181 474
Total number of attributed warrants	1 197 554
Total number of convertible bonds outstanding	828
Total number of remaining convertible bonds commitments	12
Total number of shares with voting rights that can be issued following the exercise of the attributed warrants, remaining convertible bonds commitments and the conversion of the convertible bonds	19 213 764 (1)

(1)

• 1 197 554 shares could be issued in case all 1 197 554 attributed warrants were exercised.
• 285 714 shares could be issued in case all 800 convertible bonds outstanding, issued in the private placement on 6 May 2020, were converted into shares based on the predetermined conversion price of EUR 7.00.
• 17 730 496 shares could be issued in case all 12 convertible bonds commitments remaining and all 28 convertible bonds outstanding of the ABO convertible bonds program signed on 30 May 2022 were exercised and converted into shares based on the conversion price of EUR 0.1128 (95% of the Volume-Weighted-Averaged-Price of BioSenic's shares on September 28, 2023).

About BioSenic

BioSenic is a leading biotech company specializing in the development of clinical assets issued from: (i) the arsenic trioxide (ATO) platform (with key target indications including Graft-versus-Host Disease (GvHD), systemic lupus erythematosus (SLE) and systemic sclerosis (SSc)) and (ii), the development of innovative products to meet unmet needs in orthopedics.

Following a reverse merger in October 2022, BioSenic combined a strategic positionings and strengths to use, separately and combined, an entirely new arsenal of various anti-inflammatory and anti-autoimmune formulations using the immunomodulatory properties of ATO/oral ATO (OATO) with its innovative cell therapy platform and strong IP for tissue repair protection.

BioSenic is based in the Louvain-la-Neuve Science Park in Mont-Saint-Guibert, Belgium. Further information is available at http://www.biosenic.com.

About BioSenic technology platforms

PRESS RELEASE – REGULATED INFORMATION 05/10/2023

BioSenic's technology is based on two main platforms:

• 1) The ATO platform, which has been successfully developed, has immunomodulatory properties with fundamental effects on the activated cells of the immune system. The first effect is the increase of the cell oxidative stress in activated B, T and other cells of the innate/adaptative immune system to the point they will enter a cell death program (apoptosis) and be eliminated. The second effect is potent immunomodulatory properties on several cytokines involved in inflammatory or autoimmune cell pathways, with return to homeostasis. One direct application is its use in onco-immunology to treat GvHD (Graft-versus-Host Disease) in its chronic, established stage. cGvHD is one of the most common and clinically significant complications affecting long-term survival of allogeneic hematopoietic stem cell transplantation (allo-HSCT). cGvHD is primarily mediated by the transplanted immune cells that can lead to severe multiorgan damage. BioSenic has been successful in a Phase II trial with its intravenous formulation, which has orphan drug designation status by FDA and EMA. The Company is heading towards an international Phase III confirmatory study, with its new, IP-protected, OATO formulation. Another selected target is moderate-to-severe forms of systemic lupus erythematosus (SLE), using the same oral formulation. ATO has shown good safety and significant clinical efficacy on several affected organs (skin, mucosae and the gastrointestinal tract) in an early Phase IIa study. Systemic sclerosis is also part of the clinical pipeline of BioSenic. This serious chronic disease badly affects skin, lungs or vascularization, and has no actual current effective treatment. Preclinical studies on pertinent animal models are positive, giving good grounds to launch a Phase II clinical protocol.
• 2) The allogeneic cell and gene therapy platform developed by BioSenic, with differentiated bone marrow sourced Mesenchymal Stromal Cells (MSCs), which can be stored at the point of use in hospitals. ALLOB represents a unique and proprietary approach to organ repair and specifically to bone regeneration, by turning undifferentiated stromal cells from healthy donors into bone-forming cells on the site of injury. ALLOB has recently been evaluated in a randomized, double-blind, placebo-controlled Phase IIb study in patients with high-risk tibial fractures, using its optimized production process, after a successful first safety and efficacy study (Phase 1/2a) on fractured long bones, with late-delayed union. However, in June 2023, BioSenic decided to suspend its interventional trial on fracture healing using ALLOB, following negative results obtained for the primary endpoint in this exploratory Phase IIb clinical trial, interpreted as a failure of a too early cell injection, just after fracture. BioSenic is now focusing on determining the best time to optimise the efficacy of ALLOB (choice between early or late treatment).

Note: Biosenic has reevaluated a previous important and years-long clinical development program. In March 2023, after the clinical identification of distinct OA subtypes, BioSenic delivered a new post-hoc analysis of its Phase III JTA-004 trial on knee OA, demonstrating positive action on the most severely affected patient subpopulation. This new post-hoc analysis drastically changes the therapeutic profile of the combined components and allows for better patient targeting in future clinical developments. This leads to a next generation of JTA, off-the-shelf enhanced viscosupplement to treat knee osteoarthritis (OA), made of a unique combination of mammalian plasma proteins, derivatives of hyaluronic acid (a natural component of synovial fluid in the knee) and a third active component. JTA or some derivatives are intended to provide effective lubrication and protection to the cartilage of the arthritic joint and to alleviate osteoarthritic (OA) pain and inflammation.

The company, will nevertheless focus its present R&D and clinical activities on a selective, accelerated development of its autoimmune (ATO/OATO) platform.

For further information, please contact:

BioSenic SA François Rieger, PhD, Chief Executive Officer Tel: +33 (0)671 73 31 59 investorrelations@biosenic.com

International Media Enquiries: IB Communications Neil Hunter / Michelle Boxall Tel: +44 (0)20 8943 4685 neil.hunter@ibcomms.agency / michelle@ibcomms.agency

For French Investor Enquiries: Seitosei Actifin Ghislaine Gasparetto Tel: +33 (0)1 56 88 11 22 ggasparetto@actifin.fr

Certain statements, beliefs and opinions in this press release are forward-looking, which reflect the Company or, as appropriate, the Company directors' current expectations and projections about future events. By their nature, forward-looking statements involve a number of risks, uncertainties and assumptions that could cause actual results or events to differ materially from those expressed or implied by the forward-looking statements. These risks, uncertainties and assumptions could adversely affect the outcome and financial effects of the plans and events described herein. A multitude of factors including, but not limited to, changes in demand, competition and technology, can cause actual events, performance or results to differ significantly from any anticipated development. Forward looking statements contained in this press release regarding past trends or activities should not be taken as a representation that such trends or activities will continue in the future. As a result, the Company expressly disclaims any obligation or undertaking to release any update or revisions to any forward-looking statements in this press release as a result of any change in expectations or any change in events, conditions, assumptions or circumstances on which these forward-looking statements are based. Neither the Company nor its advisers or representatives nor any of its subsidiary undertakings or any such person's officers or employees guarantees that the assumptions underlying such forward-looking statements are free from errors nor does either accept any responsibility for the future accuracy of the forward-looking statements contained in this press release or the actual occurrence of the forecasted developments. You should not place undue reliance on forward-looking statements, which speak only as of the date of this press release.